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[panhead1]

I think i am getting some piston slap from new pistons.  Thought they were bored to big but were right on.  I can take the pistons when connected to the rod and move left to right and get a .025 gauge in there.  Front to back doesn't really slide but i can rock it back and forth pushing down on the valve pockets and move it about the same.  These are wiesco pistons.  I put the same set up in my other bike and don't remember them being like that.  Any ideas?  Not sure what else to check.  This was the only thing that was really changed when i took the bike apart and went through the engine.  Put about 120 miles on the motor trying to figure out what the noise was.  

Ran mls cometic head gaskets also.  There was oil sitting in both pistons when i took it apart.  There was some oil on the inside of the head gaskets by the dowls.  I am thinking it was maybe leaking from there, but it wasn't leaking outside the head only to the inside.  Not sure if it is really blow by from the piston or not.  There was no oil that i found in either one of the exhaust valves but the front intake valve and intake itself had oil in it.  I put the harley vitron seals in the heads when i had them apart and lapped them.  

[HD Street Performance]

You need to check the cylinders (or have it done) with a dial bore gauge, inside mike the piston, and do that in torque plates.
The piston must be miked at the "gauge point"

[panhead1]

I did take it down and have the pistons and the bore checked with a gauge.  Just didn't have the torque plates.  The piston and the bore match up at almost .0025 fitment if you measure on the skirt of the piston.  I was just saying that with the rings on and in the jugs.  I can move the piston quite a bit.  I can get the .025 gauge all the way around on the top of the piston to the first ring.  Can just push it side to side to get in in left and right.  I have to pivot the piston kind of up and down to get the measurement for the front and back of the piston.  In the cylinder i can rock the piston back and forth enough to make some pretty good noise.  Pretty much what i think i was hearing when it was running.  When i had them mic the piston it was 3.883 and the bore was 3.885.  without the torque plates though.  Thats why i am stumped why i can move the piston so much when its at spec.    

[HD Street Performance]

Only a portion of the skirt is close to the wall (cold), not the top above the rings, that is grossly smaller than the bore.
.0025 is a lot of clearance for cast pistons but right on or close for a forged piston. If those are cast pistons and if your gauges are measured accurately and calibrated the skirt is collapsed.
I prefer to use a tenth reading dial bore gauge and measure the clearance (the difference) zeroing the bore gauge then measuring the mike after miking the gauge point on the skirt. This gives an accurate clearance number and calibration becomes less critical. With plates installed the whole bore can be surveyed.
Feeler gauges have uses in other parts of the motor, not checking piston to wall IMHO
  

[AXIL]

    With all do respect, take it to some one can do it right

[HILLSIDECYCLE.COM]

The skirt diameter is what you need. Forget about the top, as the ring pack stabilizes that.
Once that dimension is known, then a dial bore guage is set with the proper clearence.
The top of the piston is MUCH smaller, and round, where the skirt is barrel-shaped, and usually tapered.
Scott

[prodrag1320]

exactly,have someone check them that can torque plate them too

[HILLSIDECYCLE.COM]

 
Scott

[HD Street Performance]

 
 
Don